Aryl derivs

Very small quantities of bismuthine are obtained when a bismuth-magnesium alloy, BijMgj, is dissolved in hydrochloric acid. As would be expected, it is extremely unstable, decomposing at room temperature to bismuth and hydrogen. Alkyl and aryl derivatives, for example trimethylbismuthine, Bi(CHj)3, are more stable. 

Pseudo-saccharin ethers. When pseudo-saccharin chloride is heated with an excess of a phenol, 0-aryl derivatives of saccharin are produced (compare Section 111,27, 7). 

Alkylselenazoles are oily alkaline liquids possessing a smell similar to that of the corresponding thiazole or pyridine derivatives. The crystalline picrates or 3-methylselenazolium iodides have been used for the purpose of characterization. Alkyl derivatives are partially soluble in water aryl derivatives are insoluble. 

With the exception of the nuclear amination of 4-methylthiazole by sodium amide (341, 346) the main reactions of nucleophiles with thiazole and its simple alkyl or aryl derivatives involve the abstraction of a ring or substituent proton by a strongly basic nucleophile followed by the addition of an electrophile to the intermediate. Nucleophilic substitution of halogens is discussed in Chapter V. 

The 5-aryl derivatives have been prepared in a similar way from substituted phenylbromoacetonitrile (239), R = phenyl, X = Br. 

Organometallic compounds contain a carbon-metal bond They are named as alkyl (or aryl) derivatives of metals... 

Ketenes c=c=o 2060-2040 (vs) 1130 (s) 1374 (s) 1120 (s) Pseudo-asymmetric stretching Pseudo-symmetric stretching Alkyl derivatives Aryl derivatives... 

Mass spectral fragmentation patterns of alkyl and phenyl hydantoins have been investigated by means of labeling techniques (28—30), and similar studies have also been carried out for thiohydantoins (31,32). In all cases, breakdown of the hydantoin ring occurs by a-ftssion at C-4 with concomitant loss of carbon monoxide and an isocyanate molecule. In the case of aryl derivatives, the ease of formation of Ar—NCO is related to the electronic properties of the aryl ring substituents (33). Mass spectrometry has been used for identification of the phenylthiohydantoin derivatives formed from amino acids during peptide sequence determination by the Edman method (34). 

Ai lepiesents an aiyl group. Diaiyl products are obtained after long reaction times. Other Friedel-Crafts catalysts, eg, ZnCl2, FeCl2, FIF, and BF, can also be used. In most cases, stoichiometric amounts of the catalyst ate requited. Flowever, strong complexation of the phosphine by the catalyst necessitates separation by vacuum distillation, hydrolysis, or addition of reagents such as POCl to form more stable aluminum chloride complexes. Whereas yields up to 70—80% are possible for some aryl derivatives, yields of aliphatic derivatives are generally much less (19). 

The addition of 2,2, 4,4, 6-pentanitro-6 -methyldiphenylamine [64653-47-0] to seawater precipitates potassium (38). Aromatic amines, especially aminotetrahydronaphthalenes and their A[-aryl derivatives, are efficient flotation agents for quartz. The use of DPA for image formation in films has been patented (39,40). Diarylamines are used as intermediates (41) for azo, sulfur, oxidative base, triaryhnethane, oxazine, nitro, and safranine dyes (see Dyes and DYE INTERLffiDIATES). 

The A/-alkyl and W-cyclohexyl derivatives of sulfamic acid are comparatively stable. The A/-aryl derivatives are very unstable and can only be isolated ia the salt form. A series of thia2olylsulfamic acids has been prepared. 

Thiophene [110-02-1] and a number of its derivatives are significant in fine chemical industries as intermediates to many products for pharmaceutical, agrochemical, dyestuffs, and electronic appHcations. This article concentrates on the industrial, commercial, and economic aspects of the production and apphcations of thiophene and thiophene derivatives and details the main synthetic schemes to the parent ring system and simple alkyl and aryl derivatives. Functionalization of the ring and the synthesis of some functional derivatives that result, not from the parent ring system, but by direct ring cyclization reactions are also considered. Many good reviews on the chemistry of thiophene and thiophene derivatives are available (1 7). 

The first -PDA antiozonants were low molecular weight -diaLkyl-/)-PDAs which caused skin irritations. Current higher molecular weight -dialkyl or A/-alkyl-AT-aryl derivatives are not primary skin irritants. A notable exception is A/-(I-methylethyl)-A7-phenyl-/)-PDA, which causes dermatitis. However, since some individuals are more sensitive than others, antiozonants should always be handled with care (46). When skin contact does occur, the affected area should be washed with mild soap and water. In case of eye contact, flush weU with water. Inhalation of mbber chemicals should be avoided, and respiratory equipment should be used in dusty areas. 

IV-Alkyl substituted ureas usually eliminate the IV-substituted amine (80JHC235), but IV-arylthioureas may give ring IV-aryl derivatives 66UC447). 

The glycidyl adducts are skin irritants similar in behaviour in this respeet to the parent amines. The skin sensitisation effects in the primary aliphatic amine may be reduced by addition of groups at the nitrogen atom. The hydroxyethyl group and its alkyl and aryl derivatives are the most effective found so far. 

Since this bloom is brittle, it is broken by flexing. Therefore, waxes only protect under static conditions. For serving conditions which involve continuous flexing, /j-phenylenediamines (A, A -alkyl-aryl derivatives) can be added. These chemical antiozonants scavenge the ozone before it reacts with the rubber. A barrier of ozonized products is created which protects both the rubber and antiozonant from further attack. However, p-phenylenediamines are staining compounds. Whenever colour is an important concern, blends of elastomers can be used elastomers loading should be higher than 30 phr to provide sufficient effectiveness. 

The insertion of calcium atoms into vinyl and aryl carbon-fluorine bonds has been reported Only the resulting organometallic from the aryl derivatives appears to live long enough to be trapped by water [J]... 

It is notable that the preparation of alkyl and aryl derivatives from Pb starting materials always results in Pb organometallic compounds. The only well-defined examples of Ptf ... 

Stabilization of /j -alkyl and -aryl derivatives of transition metals can be enhanced by the judicious inclusion of various other stabilizing ligands in the complex, even though such ligands are known not to be an essential prerequisite. Particularly efficacious are potential IT acceptors (see below) such as AsPh3, PPh3,... 

Corresponding aryl derivatives are rare and unstable. Thus, while AuMe3 decomposes above —35°C but is stabilized in [AuMe3(PPh3)J, AuPh3 is unknown. 

Alkyl and 6-aryl derivatives of 3,5-dioxo-2,3,4,5-tetrahydro-l,2,4-triazine or of its thio analogs have been mentioned before in this review (e.g., Section II,B,2,a). Some of theih contained functional... 

Heating arylamines with carbon dioxide at 200 C (8500 atm) gives good yields of 3-aryl derivatives of 2,4-dihydroxyquinazoline ° (see 5e). The method is unsatisfactory when riitro, halo, and phenolic anilines and a- or p-naphthylamines are used. 

---